The real difference between cologne and perfume
Perfume or parfum is a mixture of fragrant essential oils or aroma compounds, fixatives and solvents used to give the human body, animals, food, objects, and living spaces "a pleasant scent". Perfumes have been known to exist in some of the earliest human civilizations, either through ancient texts or from archaeological digs. Modern perfumery began in the late 19th century with the commercial synthesis of aroma compounds such as vanillin or coumarin, which allowed for the composition of perfumes with smells previously unattainable solely from natural aromatics alone. Perfume types reflect the concentration of aromatic compounds in a solvent, which in fine fragrance is typically ethanol or a mix of water and ethanol. Various sources differ considerably in the definitions of perfume types. The intensity and longevity of a perfume is based on the concentration, intensity and longevity of the aromatic compounds (natural essential oils/perfume oils) used. As the percentage of aromatic compounds increases, so does the intensity and longevity of the scent created. Specific terms are used to describe a fragrance's approximate concentration by percent/volume of perfume oil, which are typically vague or imprecise.
Perfume extract, or simply perfume (extrait): 15-40% aromatic compounds (typical 20%)
Esprit de Parfum (ESdP): 15-30% aromatic compounds
Eau de Parfum (EdP), Parfum de Toilette (PdT): 10-20% (typical ~15%) aromatic compounds
Eau de Toilette (EdT): 5-15% aromatic compounds (typical ~10%)
Eau de Cologne (EdC): Chypre citrus type perfumes with 3-8% aromatic compounds (typical ~5%)
Perfume mist: 3-8% aromatic compounds (typical non-alcohol solvent)
Aftershave and Splash (EdS): 1-3% aromatic compounds
A "Classical cologne" describes men's and women's fragrances "which are basically citrus blends and do not have a perfume parent". Classical colognes are different from modern colognes, where the fragrance is typically a lighter, less concentrated interpretation of a perfume.
Men's colognes are also different from women's colognes. Men's colognes have a similar concentration to eau de toilette, eau de parfum, "and in some instances perfume"; women's colognes, on the other hand, are often the lightest concentration from a line of women's fragrance products.